Mesa was the precursor to the later language Cedar.
Due to these historic links, trained Mesa programmers from Xerox are well versed in the fundementals of GUIs, networked environments and the other advances that Xerox contributed to the field of Computer Science.
Mesa can be viewed as cross between Pascal and C. It was designed to embrace the concept of Abstract Data Types and Structured Programming.
It was well beyond its time, supporting concepts like incremental compilation and being used in environments that enabled the source code of an properly built application to assembled from anywhere in the Xerox intranet. This way any Mesa developer could debug any problems in the operating systems on Xerox 8010 and 6085 machines, which were also coded in Mesa.
Before that time Mesa was run on Xerox's own stack-based workstations such as the Alto, the 8010 (Dandilion) and the smaller and faster 6085 (Daybreak). A secondary operating system called the Xerox Development Environment (XDE) allowed developers to debug the ViewPoint GUI operating system by swapping worlds, therefore allowing crashes that would have paralysed the whole system to be debugged.
Mesa was taught via the Mesa Programming Course that took people through the wide range of technology that Xerox had available at the time and that finished off with the programmer writing a "hack", a workable programme designed to useful. An actual example of such a hack is the BWSMagnifier, which was written in 1988 and allowed people to magnify sections of the workstation screen as defined by a resizable window and a changeable magnification factor.
As ViewPoint Desktop became GlobalView and was ported to various Unix platforms, such as SunOS Unix and AIX Unix, Mesa was compiled to C and the C was then compiled for the relevant platform.
In 1976 Niklaus Wirth found the inspiration for Modula-2 during a sabbatical at Xerox Parc, where he discovered Mesa.
The Ada programming language was allegedly tendered in the hope that Xerox would write it but this was not to be the case. Despite this many ideas were taken from Mesa, although Ada is a far more verbose language and lacks Mesa's elegance.